This invention relates in general to content delivery and, more specifically, to delivering a program in a conditional access system.
Content is delivered by satellite, microwave, UHF, VDSL, optical fiber, VHF, or cable to the set top boxes of users in a number of different ways. Most content is available according to a linear schedule published in programming guides. Certain additional services are available with some of these delivery systems, for example, pay per view (PPV), video on demand (VOD) and near video on demand (NVOD). PPV allows a user to purchase the right to view a program according to a linear schedule. VOD provides the ability to view a program at any time with control of the playback by the user. NVOD is a hybrid approach where a program is available on a number of channels in a linear program with staggered start times, but the user cannot control playback.
PPV, VOD and NVOD store the content remote from the user for delivery on a dedicated or shared channel. PPV and NVOD are broadcast according to a linear schedule and multiple users share that single channel to view the program simultaneously. Because the single channel is shared, no user can control the playback of the content. In contrast, conventional VOD is singlecasted on a dedicated channel available to a single user, which allows control of the playback. For example, a user can start, stop, rewind, fast forward, or pause a VOD program.
Authorization of VOD programs is performed in conditional access systems. In a store-and-forward system, authorization is obtained from a credit amount on the set top box. Deductions from this credit are reconciled periodically such as once a day with a modem connection to the headend. Other systems query the headend whenever a VOD program is requested to provide authorization before allowing the user to watch the program.
In the appended figures, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.